Ejecting device for use in metal forging machine

ABSTRACT

An ejecting device for use in a metal forging machine which has an ejector pin and a rocking arm exerting an ejecting motion on the ejector pin by its rocking motion. The rocking motion of the rocking arm is caused by the action of a pair of rotary cams rotated by receiving rotation of a crank shaft of the machine. The action of the pair of cams is transmitted to the rocking arm through first and second rocking members connected with each other through a link, an up and down moving element and a plurality of guide rollers.

United States Patent 191 Dycke et al.

[45] Dec. 23, 1975 EIEC'I'ING DEVICE FOR USE IN METAL FORGING MACHINE [75] Inventors: Norbert Dycke,

BadenWm-ttemberg, Germany;

3 Hiroshi Sakai, Komatsu, Japan [73] Assignee: Kaisha Komatsu Seisaitusho, Japan [22] Filed: Oct. 24, 1974 [21 Appl. No; 517,145

[30] Foreign Application Priority Data Oct. 24, I973 Japan 48-! l8895 [52] US. Cl. 72/345 [51] Int. Cl. B21D 45/00 [58] field of Search 72/344, 345, 346, 427, 72/361; 83/127 [56] References Cited UNITED STATES PATENTS 3,238,761 3/l966 Hoyt 72/345 3,364,721 [H968 Criblez 72/345 Primary Examiner-Milton S. Mehr Attorney, Agent, or Firm-Armstrong, Nikaido & Wegner ABSTRACT An ejecting device for use in a metal forging machine which has an ejector pin and a rocking arm exerting an ejecting motion on the ejector pin by its rocking motion. The rocking motion of the rocking arm is caused by the action of a pair of rotary cams rotated by receiving rotation of a crank shaft of the machine. The action of the pair of cams is transmitted to the rocking arm through -fil'St and second rocking mem- A bers connected with each other through a link, an up and down moving element and a plurality of guide rol- Iers.

1 Claim, 5 Drawing Figures US. Patent Dec. 23, 1975 Sheet 1 of4 3,927,549

U.S. Patent Dec. 23, 1975 Sheet2of4 3,927,549

US. Patent Dec. 23, 1975 Sheet 3 of4 3,927,549

US. Patent Dec.23, 1975 Sheet40f4 3,927,549

EJECTING DEVICE FOR USE IN METAL FORGING MACHINE BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to an ejecting device for use in a metal forging machine, and more particularly to an improvement of an ejecting device for use in a horizontal type of multi-stage metal forging machine, for exampie, for automatically manufacturing bolts from a lengthy metal rod.

2. Description of the Prior Art A conventional ejecting device for use in a metal forging machin has such a construction that a rocking arm rockably mounted on a slide, which is reciprocated in response to rotation of a crank shaft, comes into contact with the periphery of a translation cam, which is fixed adjustably to the distal end of the machine frame, through a guide roller rotatably mounted on the upper end of the rocking arm, on the other hand, the rocking arm also comes into contact with an ejector pin slidably inserted into a punch, which is fixedly secured to the distal end of the slide, through a guide roller rotatably mounted on the lower end of the rocking arm, wherein since the upper guide roller of the rocking arm rollingly moves along the periphery of the translation cam when the slide is reciprocated in response to the rotation of the cranck shaft, the rocking arm is rocked forwards and backwards in the reciprocational direction of the slide, thus the ejector pin is ejected by the lower guide roller of the rocking arm.

In the above described conventional ejecting device, however, since the stroke timing and the amount of stroke of the ejector pin depends upon the stroke of the slide, and since the amount of stroke of the slide varies in response to a rotation angle of the crank shaft, it is very troublesome to have the stroke timing and the amount of stroke of the ejector pin. Because, these are settled by defining a shape of the translation cam depending upon the amount of stroke of the slide which is calculated from the rotation angle of the crank shaft.

In addition, since the amount of stroke of the slide becomes small at the time when the crank shaft is positioned about the lower dead point in its rotation, the amount of stroke of the ejector pin becomes also small, thereby taking a long time to knock out a product by the ejector pin.

SUMMARY OF THE INVENTION The present invention contemplates to eliminate the above described disadvantages of the conventional ejecting device.

It is, therefore, a primary object of the present invention to provide a novel ejecting device for use in a metal forging machine which can eject a ejector pin provided therein to knock out products manufactured by the machine regardless the reciprocation of the slide of the machine, thereby saving time required to knock out products.

It is another object of the present invention to provide a novel ejecting device for use in a metal forging machine in which the stroke timing and the amount of stroke of the ejector ejector pin are selectively settled by such a simple operation as adjusting the setting position of cams with respect to the cam shaft where the cams are mounted rotatably so that the ejector pin can effectively knock out products.

According to one aspect of the present invention, there is provided an ejecting device for use in a metal forging machine including therein an ejector pin slidably inserted into the distal end of a slide reciprocated in response to rotation of a crank shaft provided within the machine and a L-shaped rocking arm having upper and lower guide rollers at each end thereof and rockably mounted on the slide through a pivotal shaft to exert an ejecting motion on the ejector pin, which comprises a pair of rotary cams rotatably mounted on a cam shaft, which is rotatably supported by a frame of the device and is rotated by receiving rotation of the crank shaft, a pair of first and second triangular rocking members, each being rockably supported by the device frame through a pivotal shaft at each apex portion thereof, which are connected with each other through a link at their respective second apex portions and are arranged in such a manner that the respective four pivotal shafts for supporting the rocking members and the link are positioned at respective four corner edges of a parallelogram, a guide roller rotatably mounted on the first rocking member through an integral bracket extending from the third apex portion of the first rocking member so that the guide roller is guided the respective outer peripheries of the pair of rotary cams when the pair of rotary cams are rotated, and up and down moving element movably suspended between the first and second triangular rocking members at their respective third apex portions and coming into contact with the rocking arm at the underside flat surface thereof through the upper guide roller of the rocking arm, wherein the rocking motion of the rocking arm exerting the ejecting motion on the ejector pin is caused by the action of the pair of rotary cams, whereby the ejecting motion of the ejector pin may be done regardless the reciprocation of the slide.

BRIEF EXPLANATION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings in which:

FIG. 1 is a schematic partially cross sectional side view of a conventional ejecting device for use in a metal forging machime,

FIG. 2 is a schematic partially cross sectional side view of one embodiment of the ejecting device according to the present invention,

FIG. 3 is a schematic partially cross sectional plane view showing a drive mechanism of a cam shaft of the device of the present invention,

FIG. 4 is a fragmental partially cross sectional front view showing a main part of the device shown in FIG. '2, and

FIG. Sis a fragmental plane view showing a main part of the device shown in FIG. 4.

DETAILED DESCRIPTION OF THE INVENTION For better understanding of the present invention, a conventional ejecting device for use in a metal forging machine will now be described with reference to FIG.

As shown in FIG. I, a L-shaped rocking arm d provided with upper and lower guide rollers b and c at their respective upper and lower ends is rockably mounted on a slide a through a pivotal shaft e. The upper roller b comes into contact with a cam face h of a translation cam g adjustabiy secured to the machine frame f, while 3 the lower roller c comes into contact with the proximal end of an ejector pin j slidably inserted into the distal end of the slide a and a punch 1 attached to the distal end face of the slide.

In such construction, when the slide a is reciprocated in response to rotation of a crank shaft (not shown) provided within the machine, the upper roller b is rollingly moved along the cam face h so that the rocking arm d is rocked forwards or backwards in the reciprocating direction of the slide a about the pivotal shaft e. As a result, the ejector pin j is ejected by the lower roller 0. Thus, in the conventional device, the ejection timing and the ejection stroke of the ejector pin depends upon the reciprocation of the slide.

Reference is now made to FIGS. 2 to 5, one embodiment of the ejecting device of the present invention is described as follows:

A slide 1 of a metal forging machine is connected with an eccentric part of a crank shaft 3 through a connecting rod 2 so that the slide 1 is reciprocated in response to rotation of the crank shaft 3. The slide 1 is provided through an attachment 4 with a punch 5 at the distal end thereof and a L-shaped rocking arm 6 which is mounted thereon through a pivotal shaft 7 so as to rock forwards and backwards in a reciprocating direction of the slide 1 about the shaft 7. The rocking arm 6 is provided at the lower end thereof with a lower guide roller 9 which is rotatably mounted on a shaft 10 supported by the rocking arm 6, while at the upper end thereof with an upper guide roller 1 l which is rotatably mounted on a shaft 12 supported by the rocking arm 6 also. The lower guide roller 9 comes into contact with the proximal end of an ejector pin 8 inserted into the distal end of the slide 1 and the punch 5. Further, the rocking arm 6 is urged counterclockwise by a biasing force of a spring 13 through an urging rod 14. Reference numeral 15 represents a cam shaft rotatably supported by a frame 160 of the device. 0n the cam shaft 15, a pair of first and second rotary earns 17 and 18, which closely adhere to each other, are so mounted as to rotate together with the cam shaft 15 and to be adjustable on the position thereof with respect to the cam shaft 15. The first and second rotary earns 17 and 18 come into contact with a first triangular rocking member 20 through a guide roller 21 which is rotatably mounted on a shaft 21a supported by an integral bracket 20a extending from one apex portion of the first triangular rocking member 20. The first rocking member 20 is rockably mounted on the device frame 16a through a pivotal shaft 19 supported by the frame 160 and is connected by the interposition of a link 22 with a second triangular rocking member 24 which has the same shape as that of the first member 20 and is rockably mounted on the frame 160 through a pivotal shaft 23 supported by the frame 16a. The link 22 is connected between the first and second rocking members 20 and 24 through respective pivotal shafts 25 and 26 supported by the first and second rocking members, respectively, and the pivotal shafts 25 and 26 are disposed at respective upper apex portions of the first and second rocking members 20 and 24, so that the first and second rocking members 20 and 24 carry out the same rocking motion simultaneously with each other as a pair in which the respective four pivotal shafts 19, 23, 25 and 26 are positioned at respective four corner edges of a parallelogram. An U-shaped up and down moving element 27 is suspended between the first and second rocking members 20 and 24 at both upper end portions thereof through pivotal shafts 28 and 29, which are respectively supported by the first and second rocking members at their respective front apex portions, and come into contact with the upper guide roller 11 of the rocking arm 6 at the underside flat surface 270 thereof.

As shown in FIG. 3, tha cam shaft 15 is connected with a transmission shaft 32 through conical gears 30 and 31 screwed on the cam shaft 15 and the transmission shaft 32, respectively. The transmission shaft 32 is connected with another transmission shaft 34 through an universal joint 33. The transmission shaft 34 is connected with the crank shaft 3 through conical gears 35 and 36 screwed on the transmission shaft 35 and the crank shaft 3, respectively.

The first and second cams l7 and 18 are of plates having circular parts 17a and 18a and flat parts 17b and 18b at their respective outer peripheries.

The operation of the above constructed ejecting device of the present invention is described as follows.

When the crank shaft 3 is rotated, the slide 1 is reciprocated, at the same time, the cam shaft 15 is also rotated, and accordingly the pair of the first and second rotary cams 17 and 18 are rotated. As a result, the first rocking member 20 is rocked counterclockwise about the pivotal shaft 19 because the guide roller 21 of the first rocking member 20 is pushed down by the respective circular peripheries 17a and 18a of the first and second rotary cams, respectively, simultaneously the second rocking member 24 is rocked in the same direction as the first rocking member 20 through the link 22, so that the up and down moving element 27 is moved downwards. in this case, since the respective pivotal shafts 19, 23, 25 and 26 are positioned at respective corner edges of a parallelogram, the moving element 27 is vertically moved downwards. By this movement of the up and down moving element 27, the rocking arm 6 is rocked clockwiae through the upper guide roller 11 thereof. Thus, the ejector pin 8 is ejected forwards by the lower guide roller 9 of the rocking arm 6, thereby knocking out a product.

In addition, the ejection timing of the ejector pin 8 is preferably adjusted with respect to the rotation angle of the crank shaft 3 by varying the correlative position between the pair of first and second rotary cams 17 and 18 and the cam shaft 15 by rotating at a certain angle the pair of cams 17 and 18 about the cam shaft 15 independently of the shaft 15.

What is claimed is:

1. An ejecting device for use in a metal forging machine including therein an ejector pin slidably inserted into the distal end of a slide of the machine, said slide being reciprocated in response to rotation of a crank shaft provided within the machine, and a L-shaped rocking arm having upper and lower guide rollers at each end thereof and rockably mounted on the slide through a pivotal shaft so as to exert an ejecting motion on said ejector pin, which comprises a pair of rotary cams rotatably mounted on a cam shaft, which is rotatably supported by a frame of the device and is rotated by receiving rotation of said crank shaft, a pair of first and second triangular rocking members, each being rockably supported by said frame through a pivotal shaft at each first apex portion thereof, which are connected with each other through a link at their respective second apex portions and are arranged in such a manner that the respective four pivotal shafts for supporting said rocking members and said link are posithird apex portions and coming into contact with the rocking arm at the underside flat surface thereof through said upper guide roller of said rocking arm, wherein the rocking motion of said rocking arm exert ing the ejecting motion on said ejector pin is caused by the action of said pair of rotary cams, thereby causing ejecting motion of said ejector pin regardless of the reciprocation of said slide.

Q l k I! 

1. An ejecting device for use in a metal forging machine including therein an ejector pin slidably inserted into the distal end of a slide of the machine, said slide being reciprocated in response to rotation of a crank shaft provided within the machine, and a L-shaped rocking arm having upper and lower guide rollers at each end thereof and rockably mounted on the slide through a pivotal shaft so as to exert an ejecting motion on said ejector pin, which comprises a pair of rotary cams rotatably mounted on a cam shaft, which is rotatably supported by a frame of the device and is rotated by receiving rotation of said crank shaft, a pair of first and second triangular rocking members, each being rockably supported by said frame through a pivotal shaft at each first apex portion thereof, which are connected with each other through a link at their respective second apex portions and are arranged in such a manner that the respective four pivotal shafts for supporting said rocking members and said link are positioned at respective four corners of a parallelogram, a guide roller rotatably mounted on said first rocking member through an integral bracket extending from the third apex portion of said first rocking member so that said guide roller is guided by the respective outer peripheries of said pair of rotary cams when said pair of rotary cams are rotated, and an up and down moving element movably suspended between said first and second triangular rocking members at their respective third apex portions and coming into contact with the rocking arm at the underside flat surface thereof through said upper guide roller of said rocking arm, wherein the rocking motion of said rocking arm exerting the ejecting motion on said ejector pin is caused by the action of said pair of rotary cams, thereby causing ejecting motion of said ejector pin regardless of the reciprocation of said slide. 